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authorJulien Cristau <jcristau@debian.org>2010-07-03 19:47:55 +0100
committerJulien Cristau <jcristau@debian.org>2011-10-21 20:37:51 +0200
commit6ff0bcfcc0eb02640456beacaaa93ee762c84507 (patch)
tree1df0ea04c290165f6b62ce492951e52d2308915f
parent94458a6e09761e3b7937bb639ea4c12972328c7f (diff)
glx: validate request lengths
Reviewed-by: Adam Jackson <ajax@redhat.com> Reviewed-by: Kristian Høgsberg <krh@bitplanet.net> Reviewed-by: Daniel Stone <daniel@fooishbar.org> Signed-off-by: Julien Cristau <jcristau@debian.org> (cherry-picked from commit ec9c97c6bf70b523bc500bd3adf62176f1bb33a4)
-rw-r--r--glx/glxcmds.c142
-rw-r--r--glx/xfont.c2
2 files changed, 135 insertions, 9 deletions
diff --git a/glx/glxcmds.c b/glx/glxcmds.c
index 3eae1aac7..b8ee546fd 100644
--- a/glx/glxcmds.c
+++ b/glx/glxcmds.c
@@ -312,11 +312,14 @@ DoCreateContext(__GLXclientState *cl, GLXContextID gcId,
int __glXDisp_CreateContext(__GLXclientState *cl, GLbyte *pc)
{
+ ClientPtr client = cl->client;
xGLXCreateContextReq *req = (xGLXCreateContextReq *) pc;
__GLXconfig *config;
__GLXscreen *pGlxScreen;
int err;
+ REQUEST_SIZE_MATCH(xGLXCreateContextReq);
+
if (!validGlxScreen(cl->client, req->screen, &pGlxScreen, &err))
return err;
if (!validGlxVisual(cl->client, pGlxScreen, req->visual, &config, &err))
@@ -328,11 +331,14 @@ int __glXDisp_CreateContext(__GLXclientState *cl, GLbyte *pc)
int __glXDisp_CreateNewContext(__GLXclientState *cl, GLbyte *pc)
{
+ ClientPtr client = cl->client;
xGLXCreateNewContextReq *req = (xGLXCreateNewContextReq *) pc;
__GLXconfig *config;
__GLXscreen *pGlxScreen;
int err;
+ REQUEST_SIZE_MATCH(xGLXCreateNewContextReq);
+
if (!validGlxScreen(cl->client, req->screen, &pGlxScreen, &err))
return err;
if (!validGlxFBConfig(cl->client, pGlxScreen, req->fbconfig, &config, &err))
@@ -344,12 +350,15 @@ int __glXDisp_CreateNewContext(__GLXclientState *cl, GLbyte *pc)
int __glXDisp_CreateContextWithConfigSGIX(__GLXclientState *cl, GLbyte *pc)
{
+ ClientPtr client = cl->client;
xGLXCreateContextWithConfigSGIXReq *req =
(xGLXCreateContextWithConfigSGIXReq *) pc;
__GLXconfig *config;
__GLXscreen *pGlxScreen;
int err;
+ REQUEST_SIZE_MATCH(xGLXCreateContextWithConfigSGIXReq);
+
if (!validGlxScreen(cl->client, req->screen, &pGlxScreen, &err))
return err;
if (!validGlxFBConfig(cl->client, pGlxScreen, req->fbconfig, &config, &err))
@@ -360,10 +369,13 @@ int __glXDisp_CreateContextWithConfigSGIX(__GLXclientState *cl, GLbyte *pc)
}
int __glXDisp_DestroyContext(__GLXclientState *cl, GLbyte *pc)
{
+ ClientPtr client = cl->client;
xGLXDestroyContextReq *req = (xGLXDestroyContextReq *) pc;
__GLXcontext *glxc;
int err;
+ REQUEST_SIZE_MATCH(xGLXDestroyContextReq);
+
if (!validGlxContext(cl->client, req->context, DixDestroyAccess,
&glxc, &err))
return err;
@@ -675,24 +687,33 @@ DoMakeCurrent(__GLXclientState *cl,
int __glXDisp_MakeCurrent(__GLXclientState *cl, GLbyte *pc)
{
+ ClientPtr client = cl->client;
xGLXMakeCurrentReq *req = (xGLXMakeCurrentReq *) pc;
+ REQUEST_SIZE_MATCH(xGLXMakeCurrentReq);
+
return DoMakeCurrent( cl, req->drawable, req->drawable,
req->context, req->oldContextTag );
}
int __glXDisp_MakeContextCurrent(__GLXclientState *cl, GLbyte *pc)
{
+ ClientPtr client = cl->client;
xGLXMakeContextCurrentReq *req = (xGLXMakeContextCurrentReq *) pc;
+ REQUEST_SIZE_MATCH(xGLXMakeContextCurrentReq);
+
return DoMakeCurrent( cl, req->drawable, req->readdrawable,
req->context, req->oldContextTag );
}
int __glXDisp_MakeCurrentReadSGI(__GLXclientState *cl, GLbyte *pc)
{
+ ClientPtr client = cl->client;
xGLXMakeCurrentReadSGIReq *req = (xGLXMakeCurrentReadSGIReq *) pc;
+ REQUEST_SIZE_MATCH(xGLXMakeCurrentReadSGIReq);
+
return DoMakeCurrent( cl, req->drawable, req->readable,
req->context, req->oldContextTag );
}
@@ -705,6 +726,8 @@ int __glXDisp_IsDirect(__GLXclientState *cl, GLbyte *pc)
__GLXcontext *glxc;
int err;
+ REQUEST_SIZE_MATCH(xGLXIsDirectReq);
+
if (!validGlxContext(cl->client, req->context, DixReadAccess, &glxc, &err))
return err;
@@ -729,6 +752,8 @@ int __glXDisp_QueryVersion(__GLXclientState *cl, GLbyte *pc)
xGLXQueryVersionReply reply;
GLuint major, minor;
+ REQUEST_SIZE_MATCH(xGLXQueryVersionReq);
+
major = req->majorVersion;
minor = req->minorVersion;
(void)major;
@@ -755,11 +780,15 @@ int __glXDisp_QueryVersion(__GLXclientState *cl, GLbyte *pc)
int __glXDisp_WaitGL(__GLXclientState *cl, GLbyte *pc)
{
+ ClientPtr client = cl->client;
xGLXWaitGLReq *req = (xGLXWaitGLReq *)pc;
- GLXContextTag tag = req->contextTag;
+ GLXContextTag tag;
__GLXcontext *glxc = NULL;
int error;
+ REQUEST_SIZE_MATCH(xGLXWaitGLReq);
+
+ tag = req->contextTag;
if (tag) {
glxc = __glXLookupContextByTag(cl, tag);
if (!glxc)
@@ -779,11 +808,15 @@ int __glXDisp_WaitGL(__GLXclientState *cl, GLbyte *pc)
int __glXDisp_WaitX(__GLXclientState *cl, GLbyte *pc)
{
+ ClientPtr client = cl->client;
xGLXWaitXReq *req = (xGLXWaitXReq *)pc;
- GLXContextTag tag = req->contextTag;
+ GLXContextTag tag;
__GLXcontext *glxc = NULL;
int error;
+ REQUEST_SIZE_MATCH(xGLXWaitXReq);
+
+ tag = req->contextTag;
if (tag) {
glxc = __glXLookupContextByTag(cl, tag);
if (!glxc)
@@ -803,13 +836,19 @@ int __glXDisp_CopyContext(__GLXclientState *cl, GLbyte *pc)
{
ClientPtr client = cl->client;
xGLXCopyContextReq *req = (xGLXCopyContextReq *) pc;
- GLXContextID source = req->source;
- GLXContextID dest = req->dest;
- GLXContextTag tag = req->contextTag;
- unsigned long mask = req->mask;
+ GLXContextID source;
+ GLXContextID dest;
+ GLXContextTag tag;
+ unsigned long mask;
__GLXcontext *src, *dst;
int error;
+ REQUEST_SIZE_MATCH(xGLXCopyContextReq);
+
+ source = req->source;
+ dest = req->dest;
+ tag = req->contextTag;
+ mask = req->mask;
if (!validGlxContext(cl->client, source, DixReadAccess, &src, &error))
return error;
if (!validGlxContext(cl->client, dest, DixWriteAccess, &dst, &error))
@@ -892,6 +931,8 @@ int __glXDisp_GetVisualConfigs(__GLXclientState *cl, GLbyte *pc)
__GLX_DECLARE_SWAP_VARIABLES;
__GLX_DECLARE_SWAP_ARRAY_VARIABLES;
+ REQUEST_SIZE_MATCH(xGLXGetVisualConfigsReq);
+
if (!validGlxScreen(cl->client, req->screen, &pGlxScreen, &err))
return err;
@@ -1071,13 +1112,17 @@ DoGetFBConfigs(__GLXclientState *cl, unsigned screen)
int __glXDisp_GetFBConfigs(__GLXclientState *cl, GLbyte *pc)
{
+ ClientPtr client = cl->client;
xGLXGetFBConfigsReq *req = (xGLXGetFBConfigsReq *) pc;
+ REQUEST_SIZE_MATCH(xGLXGetFBConfigsReq);
return DoGetFBConfigs(cl, req->screen);
}
int __glXDisp_GetFBConfigsSGIX(__GLXclientState *cl, GLbyte *pc)
{
+ ClientPtr client = cl->client;
xGLXGetFBConfigsSGIXReq *req = (xGLXGetFBConfigsSGIXReq *) pc;
+ REQUEST_SIZE_MATCH(xGLXGetFBConfigsSGIXReq);
return DoGetFBConfigs(cl, req->screen);
}
@@ -1203,11 +1248,14 @@ determineTextureTarget(ClientPtr client, XID glxDrawableID,
int __glXDisp_CreateGLXPixmap(__GLXclientState *cl, GLbyte *pc)
{
+ ClientPtr client = cl->client;
xGLXCreateGLXPixmapReq *req = (xGLXCreateGLXPixmapReq *) pc;
__GLXconfig *config;
__GLXscreen *pGlxScreen;
int err;
+ REQUEST_SIZE_MATCH(xGLXCreateGLXPixmapReq);
+
if (!validGlxScreen(cl->client, req->screen, &pGlxScreen, &err))
return err;
if (!validGlxVisual(cl->client, pGlxScreen, req->visual, &config, &err))
@@ -1219,11 +1267,14 @@ int __glXDisp_CreateGLXPixmap(__GLXclientState *cl, GLbyte *pc)
int __glXDisp_CreatePixmap(__GLXclientState *cl, GLbyte *pc)
{
+ ClientPtr client = cl->client;
xGLXCreatePixmapReq *req = (xGLXCreatePixmapReq *) pc;
__GLXconfig *config;
__GLXscreen *pGlxScreen;
int err;
+ REQUEST_FIXED_SIZE(xGLXCreatePixmapReq, req->numAttribs << 3);
+
if (!validGlxScreen(cl->client, req->screen, &pGlxScreen, &err))
return err;
if (!validGlxFBConfig(cl->client, pGlxScreen, req->fbconfig, &config, &err))
@@ -1242,12 +1293,15 @@ int __glXDisp_CreatePixmap(__GLXclientState *cl, GLbyte *pc)
int __glXDisp_CreateGLXPixmapWithConfigSGIX(__GLXclientState *cl, GLbyte *pc)
{
+ ClientPtr client = cl->client;
xGLXCreateGLXPixmapWithConfigSGIXReq *req =
(xGLXCreateGLXPixmapWithConfigSGIXReq *) pc;
__GLXconfig *config;
__GLXscreen *pGlxScreen;
int err;
+ REQUEST_SIZE_MATCH(xGLXCreateGLXPixmapWithConfigSGIXReq);
+
if (!validGlxScreen(cl->client, req->screen, &pGlxScreen, &err))
return err;
if (!validGlxFBConfig(cl->client, pGlxScreen, req->fbconfig, &config, &err))
@@ -1274,15 +1328,21 @@ static int DoDestroyDrawable(__GLXclientState *cl, XID glxdrawable, int type)
int __glXDisp_DestroyGLXPixmap(__GLXclientState *cl, GLbyte *pc)
{
+ ClientPtr client = cl->client;
xGLXDestroyGLXPixmapReq *req = (xGLXDestroyGLXPixmapReq *) pc;
+ REQUEST_SIZE_MATCH(xGLXDestroyGLXPixmapReq);
+
return DoDestroyDrawable(cl, req->glxpixmap, GLX_DRAWABLE_PIXMAP);
}
int __glXDisp_DestroyPixmap(__GLXclientState *cl, GLbyte *pc)
{
+ ClientPtr client = cl->client;
xGLXDestroyPixmapReq *req = (xGLXDestroyPixmapReq *) pc;
+ REQUEST_SIZE_MATCH(xGLXDestroyPixmapReq);
+
return DoDestroyDrawable(cl, req->glxpixmap, GLX_DRAWABLE_PIXMAP);
}
@@ -1311,10 +1371,13 @@ DoCreatePbuffer(ClientPtr client, int screenNum, XID fbconfigId,
int __glXDisp_CreatePbuffer(__GLXclientState *cl, GLbyte *pc)
{
+ ClientPtr client = cl->client;
xGLXCreatePbufferReq *req = (xGLXCreatePbufferReq *) pc;
CARD32 *attrs;
int width, height, i;
+ REQUEST_FIXED_SIZE(xGLXCreatePbufferReq, req->numAttribs << 3);
+
attrs = (CARD32 *) (req + 1);
width = 0;
height = 0;
@@ -1340,23 +1403,32 @@ int __glXDisp_CreatePbuffer(__GLXclientState *cl, GLbyte *pc)
int __glXDisp_CreateGLXPbufferSGIX(__GLXclientState *cl, GLbyte *pc)
{
+ ClientPtr client = cl->client;
xGLXCreateGLXPbufferSGIXReq *req = (xGLXCreateGLXPbufferSGIXReq *) pc;
+ REQUEST_SIZE_MATCH(xGLXCreateGLXPbufferSGIXReq);
+
return DoCreatePbuffer(cl->client, req->screen, req->fbconfig,
req->width, req->height, req->pbuffer);
}
int __glXDisp_DestroyPbuffer(__GLXclientState *cl, GLbyte *pc)
{
+ ClientPtr client = cl->client;
xGLXDestroyPbufferReq *req = (xGLXDestroyPbufferReq *) pc;
+ REQUEST_SIZE_MATCH(xGLXDestroyPbufferReq);
+
return DoDestroyDrawable(cl, req->pbuffer, GLX_DRAWABLE_PBUFFER);
}
int __glXDisp_DestroyGLXPbufferSGIX(__GLXclientState *cl, GLbyte *pc)
{
+ ClientPtr client = cl->client;
xGLXDestroyGLXPbufferSGIXReq *req = (xGLXDestroyGLXPbufferSGIXReq *) pc;
+ REQUEST_SIZE_MATCH(xGLXDestroyGLXPbufferSGIXReq);
+
return DoDestroyDrawable(cl, req->pbuffer, GLX_DRAWABLE_PBUFFER);
}
@@ -1387,18 +1459,24 @@ DoChangeDrawableAttributes(ClientPtr client, XID glxdrawable,
int __glXDisp_ChangeDrawableAttributes(__GLXclientState *cl, GLbyte *pc)
{
+ ClientPtr client = cl->client;
xGLXChangeDrawableAttributesReq *req =
(xGLXChangeDrawableAttributesReq *) pc;
+ REQUEST_FIXED_SIZE(xGLXChangeDrawableAttributesReq, req->numAttribs << 3);
+
return DoChangeDrawableAttributes(cl->client, req->drawable,
req->numAttribs, (CARD32 *) (req + 1));
}
int __glXDisp_ChangeDrawableAttributesSGIX(__GLXclientState *cl, GLbyte *pc)
{
+ ClientPtr client = cl->client;
xGLXChangeDrawableAttributesSGIXReq *req =
(xGLXChangeDrawableAttributesSGIXReq *)pc;
+ REQUEST_FIXED_SIZE(xGLXChangeDrawableAttributesSGIXReq, req->numAttribs << 3);
+
return DoChangeDrawableAttributes(cl->client, req->drawable,
req->numAttribs, (CARD32 *) (req + 1));
}
@@ -1412,6 +1490,8 @@ int __glXDisp_CreateWindow(__GLXclientState *cl, GLbyte *pc)
DrawablePtr pDraw;
int err;
+ REQUEST_FIXED_SIZE(xGLXCreateWindowReq, req->numAttribs << 3);
+
if (!validGlxScreen(client, req->screen, &pGlxScreen, &err))
return err;
if (!validGlxFBConfig(client, pGlxScreen, req->fbconfig, &config, &err))
@@ -1432,8 +1512,11 @@ int __glXDisp_CreateWindow(__GLXclientState *cl, GLbyte *pc)
int __glXDisp_DestroyWindow(__GLXclientState *cl, GLbyte *pc)
{
+ ClientPtr client = cl->client;
xGLXDestroyWindowReq *req = (xGLXDestroyWindowReq *) pc;
+ REQUEST_SIZE_MATCH(xGLXDestroyWindowReq);
+
return DoDestroyDrawable(cl, req->glxwindow, GLX_DRAWABLE_WINDOW);
}
@@ -1449,12 +1532,16 @@ int __glXDisp_SwapBuffers(__GLXclientState *cl, GLbyte *pc)
{
ClientPtr client = cl->client;
xGLXSwapBuffersReq *req = (xGLXSwapBuffersReq *) pc;
- GLXContextTag tag = req->contextTag;
- XID drawId = req->drawable;
+ GLXContextTag tag;
+ XID drawId;
__GLXcontext *glxc = NULL;
__GLXdrawable *pGlxDraw;
int error;
+ REQUEST_SIZE_MATCH(xGLXSwapBuffersReq);
+
+ tag = req->contextTag;
+ drawId = req->drawable;
if (tag) {
glxc = __glXLookupContextByTag(cl, tag);
if (!glxc) {
@@ -1535,15 +1622,21 @@ DoQueryContext(__GLXclientState *cl, GLXContextID gcId)
int __glXDisp_QueryContextInfoEXT(__GLXclientState *cl, GLbyte *pc)
{
+ ClientPtr client = cl->client;
xGLXQueryContextInfoEXTReq *req = (xGLXQueryContextInfoEXTReq *) pc;
+ REQUEST_SIZE_MATCH(xGLXQueryContextInfoEXTReq);
+
return DoQueryContext(cl, req->context);
}
int __glXDisp_QueryContext(__GLXclientState *cl, GLbyte *pc)
{
+ ClientPtr client = cl->client;
xGLXQueryContextReq *req = (xGLXQueryContextReq *) pc;
+ REQUEST_SIZE_MATCH(xGLXQueryContextReq);
+
return DoQueryContext(cl, req->context);
}
@@ -1557,6 +1650,8 @@ int __glXDisp_BindTexImageEXT(__GLXclientState *cl, GLbyte *pc)
int buffer;
int error;
+ REQUEST_FIXED_SIZE(xGLXVendorPrivateReq, 8);
+
pc += __GLX_VENDPRIV_HDR_SIZE;
drawId = *((CARD32 *) (pc));
@@ -1591,6 +1686,8 @@ int __glXDisp_ReleaseTexImageEXT(__GLXclientState *cl, GLbyte *pc)
int buffer;
int error;
+ REQUEST_FIXED_SIZE(xGLXVendorPrivateReq, 8);
+
pc += __GLX_VENDPRIV_HDR_SIZE;
drawId = *((CARD32 *) (pc));
@@ -1626,6 +1723,8 @@ int __glXDisp_CopySubBufferMESA(__GLXclientState *cl, GLbyte *pc)
(void) client;
(void) req;
+ REQUEST_FIXED_SIZE(xGLXVendorPrivateReq, 20);
+
pc += __GLX_VENDPRIV_HDR_SIZE;
drawId = *((CARD32 *) (pc));
@@ -1714,16 +1813,22 @@ DoGetDrawableAttributes(__GLXclientState *cl, XID drawId)
int __glXDisp_GetDrawableAttributes(__GLXclientState *cl, GLbyte *pc)
{
+ ClientPtr client = cl->client;
xGLXGetDrawableAttributesReq *req = (xGLXGetDrawableAttributesReq *)pc;
+ REQUEST_SIZE_MATCH(xGLXGetDrawableAttributesReq);
+
return DoGetDrawableAttributes(cl, req->drawable);
}
int __glXDisp_GetDrawableAttributesSGIX(__GLXclientState *cl, GLbyte *pc)
{
+ ClientPtr client = cl->client;
xGLXGetDrawableAttributesSGIXReq *req =
(xGLXGetDrawableAttributesSGIXReq *)pc;
+ REQUEST_SIZE_MATCH(xGLXGetDrawableAttributesSGIXReq);
+
return DoGetDrawableAttributes(cl, req->drawable);
}
@@ -1748,6 +1853,8 @@ int __glXDisp_Render(__GLXclientState *cl, GLbyte *pc)
__GLXcontext *glxc;
__GLX_DECLARE_SWAP_VARIABLES;
+ REQUEST_AT_LEAST_SIZE(xGLXRenderReq);
+
req = (xGLXRenderReq *) pc;
if (client->swapped) {
__GLX_SWAP_SHORT(&req->length);
@@ -1768,6 +1875,9 @@ int __glXDisp_Render(__GLXclientState *cl, GLbyte *pc)
__GLXdispatchRenderProcPtr proc;
int err;
+ if (left < sizeof(__GLXrenderHeader))
+ return BadLength;
+
/*
** Verify that the header length and the overall length agree.
** Also, each command must be word aligned.
@@ -2278,10 +2388,12 @@ int __glXDisp_HyperpipeConfigSGIX(__GLXclientState *cl, GLbyte *pc)
int __glXDisp_VendorPrivate(__GLXclientState *cl, GLbyte *pc)
{
+ ClientPtr client = cl->client;
xGLXVendorPrivateReq *req = (xGLXVendorPrivateReq *) pc;
GLint vendorcode = req->vendorCode;
__GLXdispatchVendorPrivProcPtr proc;
+ REQUEST_AT_LEAST_SIZE(xGLXVendorPrivateReq);
proc = (__GLXdispatchVendorPrivProcPtr)
__glXGetProtocolDecodeFunction(& VendorPriv_dispatch_info,
@@ -2297,10 +2409,12 @@ int __glXDisp_VendorPrivate(__GLXclientState *cl, GLbyte *pc)
int __glXDisp_VendorPrivateWithReply(__GLXclientState *cl, GLbyte *pc)
{
+ ClientPtr client = cl->client;
xGLXVendorPrivateReq *req = (xGLXVendorPrivateReq *) pc;
GLint vendorcode = req->vendorCode;
__GLXdispatchVendorPrivProcPtr proc;
+ REQUEST_AT_LEAST_SIZE(xGLXVendorPrivateReq);
proc = (__GLXdispatchVendorPrivProcPtr)
__glXGetProtocolDecodeFunction(& VendorPriv_dispatch_info,
@@ -2323,6 +2437,8 @@ int __glXDisp_QueryExtensionsString(__GLXclientState *cl, GLbyte *pc)
char *buf;
int err;
+ REQUEST_SIZE_MATCH(xGLXQueryExtensionsStringReq);
+
if (!validGlxScreen(client, req->screen, &pGlxScreen, &err))
return err;
@@ -2361,6 +2477,8 @@ int __glXDisp_QueryServerString(__GLXclientState *cl, GLbyte *pc)
__GLXscreen *pGlxScreen;
int err;
+ REQUEST_SIZE_MATCH(xGLXQueryServerStringReq);
+
if (!validGlxScreen(client, req->screen, &pGlxScreen, &err))
return err;
@@ -2404,14 +2522,20 @@ int __glXDisp_QueryServerString(__GLXclientState *cl, GLbyte *pc)
int __glXDisp_ClientInfo(__GLXclientState *cl, GLbyte *pc)
{
+ ClientPtr client = cl->client;
xGLXClientInfoReq *req = (xGLXClientInfoReq *) pc;
const char *buf;
+ REQUEST_AT_LEAST_SIZE(xGLXClientInfoReq);
+
+ buf = (const char *)(req+1);
+ if (!memchr(buf, 0, (client->req_len << 2) - sizeof(xGLXClientInfoReq)))
+ return BadLength;
+
cl->GLClientmajorVersion = req->major;
cl->GLClientminorVersion = req->minor;
if (cl->GLClientextensions)
xfree(cl->GLClientextensions);
- buf = (const char *)(req+1);
cl->GLClientextensions = xstrdup(buf);
return Success;
diff --git a/glx/xfont.c b/glx/xfont.c
index b8b466d87..5d5b4c38d 100644
--- a/glx/xfont.c
+++ b/glx/xfont.c
@@ -160,6 +160,8 @@ int __glXDisp_UseXFont(__GLXclientState *cl, GLbyte *pc)
__GLXcontext *cx;
int error;
+ REQUEST_SIZE_MATCH(xGLXUseXFontReq);
+
req = (xGLXUseXFontReq *) pc;
cx = __glXForceCurrent(cl, req->contextTag, &error);
if (!cx) {